Mr Chaotic composed using every semitone (9)

I believe the answer is:

chromatic

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'using every semitone' is the definition.
I can't tell whether this defines the answer.

'mr chaotic composed' is the wordplay.
'composed' indicates anagramming the letters.
'mr'+'chaotic'='mrchaotic'
'mrchaotic' is an anagram of 'CHROMATIC'.

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(Other definitions for chromatic that I've seen before include "With use of colour" , "in colours" , "colourful?" , "Trim coach (anag.)" .)

I've seen this clue in The Daily Express.

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